Orioles outfielder Mark Trumbo was placed on the 10-day disabled list with a right rib cage strain, the team announced Monday.
Manager Buck Showalter said Trumbo would have an MRI on Tuesday morning to determine the extent of the injury, which he was concerned could be an oblique strain.
Trumbo called it only an upper body injury Monday.
"With this type of injury, you get a pretty good idea of what you're dealing with," Showalter said.
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The club's need to activate new pitcher Jeremy Hellickson meant putting Trumbo on the disabled list before that test was administered.
Trumbo had started every game of the season before Sunday, when he was doing squats to stretch in the weight room before the game at Globe Life Park in Arlington, Texas, and tweaked his back.
He was scratched from the lineup and also was left out of Monday's lineup against the Kansas City Royals.
Trumbo, the reigning major league home run king, is having a down year by those standards, hitting the DL batting .238/.300/.405 with 17 home runs and 50 RBIs.
Hellickson, who was acquired Friday night from the Philadelphia Phillies, had to be activated by Monday. To make room for him on the 40-man roster, the Orioles transferred shortstop J.J. Hardy (fractured wrist) to the 60-day disabled list. Hardy cannot be activated until Aug. 18, though it's unclear whether he would be back by then anyway.
